After many centuries when horsemen dominate the battlefield (whether the heavily armed knights of Europe or the swift Mongols of the steppes), the early 14th century sees the reassertion of the foot soldier.

Partly this is due to new weapons - the English longbow and the Swiss halberd. But the change also involves the return of very ancient tactics. The Greek phalanx, with the long spear introduced by Alexander the Great, is revived to devastating effect by Swiss peasants armed with pikes.

The longbow: 1298-1346

The longbow, probably developed in Wales during the 12th century, derives its range, accuracy and power of penetration from two characteristics.

It is about 6 feet long, giving a much greater acceleration to the released arrow than is possible from a shorter conventional bow. And the craftsmen make it from strips of yew cut where the hardened heart of the tree joins the sap wood. The different qualities of the two types of wood complement each other, combining tension and compression as in a composite bow.

The length of the English bow makes possible a heavier arrow, a yard in length, with greater power of penetration. A trained bowman can shoot between six and ten arrows a minute, with considerable accuracy to a range of 200 yards.

The power of the longbow is first demonstrated in 1298 at Falkirk, where an English army defeats the Scots. But the Scots are mainly unmounted spearmen; the battle is fought round the edges of a boggy marsh; this is an unromantic event which does little to spread the fame of the new weapon. That must await another half century until English bowmen come up against the mounted chivalry of France at Crécy in 1346.

The fighting begins at Crécy with a direct confrontation between English longbowmen and Genoese crossbowmen, employed as mercenaries by the French king. The English, outnumbered by the French, occupy a defensive position on a slope overlooking a small valley. The battle begins when the French king orders a line of crossbowmen to advance on the English position, with mounted knights following behind them.

The English outshoot the Genoese, who need to pause to crank their crossbow after each shot. When the Genoese retreat in panic, they become entangled with the advancing French cavalry. The resulting chaos offers an easy target to the bowmen on the hill.

Subsequent charges by the French cavalry meet a similar fate in a battle which continues until nightfall. The next morning some 1500 French knights and esquires are found dead on the battlefield together with large numbers of more humble soldiers.

The English longbow proves itself at Crécy the most effective long-range weapon of its time. It dominates the field in subsequent battles of the Hundred Years' War such as Poitiers and Agincourt. But near the end of the war, at Formigny, the bowmen meet more than their match in the new form of French artillery. The weapon of the future, clumsy and awkward though it is, wins the day.

Swiss pikes and halberds: 14th - 15th century

The power of a citizen army of footsoldiers, demonstrated so forcefully in ancient Greece, is proved again two millennia later by the peasants of Switzerland. The similarity extends beyond the passion of free men fighting for their patch of land. It includes tactics and even weapons.

The Swiss adopt the Greek formation of the phalanx, a tightly cohesive square of men. And they borrow from the armies of Alexander the Great the exceptionally long spear which prevents an enemy from coming in close.

The Swiss spear or pike, some 20 feet long, improves in one respect on Greek technology. Its steel point projects from a long metal sleeve, preventing a mounted knight from slashing the wooden shaft.

The phalanx with its pikes at the ready is a defensive body, bristling like a hedgehog. When the enemy begins to falter, the Swiss change to offence. For this too they have a devastating weapon, perfected by themselves - the halberd. The pike can only prod an assailant. The halberd is much more versatile, as the Swiss footsoldiers prove triumphantly at Morgarten, in 1315, when they trap a Habsburg army in a narrow mountain defile.

The Habsburg knights, mounted and in armour, rely on the thundering weight of a charger to mow down the opposition. In the confined space of Morgarten, they find themselves at the mercy of the Swiss halberdiers.

At the end of each 8-foot halberd there is a sharp metal point; this can jab like a spear. Below the point to one side is a hook; this is used to grapple a knight and drag him from his horse. Below the point on the other side there is an axe blade; with a heavy sweeping blow, at the end of the long handle, this will cut through armour and sink into limb or neck. With this lethally adaptable weapon the Swiss footsoldiers bring down the Habsburg cavalry.

After Morgarten and other similar successes the massed phalanx of infantry, reintroduced by the Swiss, becomes once again a standard part of battlefield tactics. It is extended in Spain into the massive 'Spanish square' which combines men armed with pikes, swords and muskets.

Meanwhile the Swiss farmers have discovered in their martial skill a new profession. They begin to hire themselves out as mercenaries - in a long tradition of which there is an echo, even today, in the Swiss guards of the Vatican.